FreeCalypso > hg > gsm-codec-lib
view libgsmefr/weight_a.c @ 477:4c9222d95647
libtwamr encoder: always emit frame->mode = mode;
In the original implementation of amr_encode_frame(), the 'mode' member
of the output struct was set to 0xFF if the output frame type is TX_NO_DATA.
This design was made to mimic the mode field (16-bit word) being set to
0xFFFF (or -1) in 3GPP test sequence format - but nothing actually depends
on this struct member being set in any way, and amr_frame_to_tseq()
generates the needed 0xFFFF on its own, based on frame->type being equal
to TX_NO_DATA.
It is simpler and more efficient to always set frame->mode to the actual
encoding mode in amr_encode_frame(), and this new behavior has already
been documented in doc/AMR-library-API description in anticipation of
the present change.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sat, 18 May 2024 22:30:42 +0000 |
parents | b651adfce60d |
children |
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/************************************************************************* * * FUNCTION: Weight_Ai * * PURPOSE: Spectral expansion of LP coefficients. (order==10) * * DESCRIPTION: * a_exp[i] = a[i] * fac[i-1] ,i=1,10 * *************************************************************************/ #include "gsm_efr.h" #include "typedef.h" #include "namespace.h" #include "basic_op.h" #include "no_count.h" #include "sig_proc.h" /* m = LPC order == 10 */ #define m 10 void Weight_Ai ( Word16 a[], /* (i) : a[m+1] LPC coefficients (m=10) */ const Word16 fac[], /* (i) : Spectral expansion factors. */ Word16 a_exp[] /* (o) : Spectral expanded LPC coefficients */ ) { Word16 i; a_exp[0] = a[0]; move16 (); for (i = 1; i <= m; i++) { a_exp[i] = round (L_mult (a[i], fac[i - 1])); move16 (); } return; }